Outcrop of Muschelkalk dolomite crosscut by a dark vein of impact melt rock in the vicinity of Monforte de Moyuela.
Black vein under the microscope: light matrix of carbonate minerals (Cc), black particles and gas vesicles (gv). Long side of the figure is about 1 mm.
The full article can be read here:
http://www.uni-wuerzburg.de/mineralogie/schuessler/Monforte-vein.pdf
key words: Azuara impact structure, Rubielos de la Cérida impact structure, carbonate melt, breccia dike, manganese, quench crystallization.